feat(infra): production bootstrap — cert-manager, longhorn, monitoring

Add new bases for cert-manager (Let's Encrypt + wildcard cert), Longhorn
distributed storage, and monitoring (kube-prometheus-stack + Loki + Tempo
+ Grafana OIDC). Add cloud-init for Scaleway Elastic Metal provisioning.

Production overlay: add patches for postgres sizing, SeaweedFS volume,
OpenSearch storage, LiveKit service, Pingora host ports, resource limits,
and CNPG daily barman backups. Update cert-manager.yaml with full dnsNames
for all *.sunbeam.pt subdomains.

overlays/production/patch-livekit-service.yaml

@@ -0,0 +1,10 @@
+# Patch: keep LiveKit TURN service as ClusterIP — Pingora routes external TURN traffic.
+# Without this patch, klipper-lb (disabled) or the default LoadBalancer type may
+# conflict with Pingora's host port bindings on port 443.
+apiVersion: v1
+kind: Service
+metadata:
+  name: livekit-server-turn
+  namespace: media
+spec:
+  type: ClusterIP